Who will Cardinals protect from Rule 5 Draft?

With Friday's deadline looming, St. Louis has decisions to make on prospects

Who will Cardinals protect from Rule 5 Draft?

ST. LOUIS -- The deadline to protect players from being plucked in the Rule 5 Draft arrives on Friday, leaving the Cardinals with some imminent decisions that will affect their roster flexibility and risk of losing Minor League players next month.

Players who were signed when they were 19 years or older and remain off a team's 40-man roster become Rule 5 eligible after four professional seasons. For those signed at a younger age, they must play five seasons before that eligibility begins.

And while that makes dozens of Minor Leaguers eligible each winter in the Rule 5 Draft, only a few actually get snatched away. That's because a team that choses a player is only guaranteed to retain that player if he remains on the selecting club's 40-man roster for a full season.

AFL Report: St. Louis Cardinals

The Cardinals have several current vacancies on their roster to make additions, though they won't fill them all. That would restrict their ability to make other additions this winter. So with interesting decisions ahead, here is a look at some Minor League players the organization may consider protecting

Aledmys Diaz
The Cuban shortstop has already exhausted two seasons of the four-year, $8-million deal he signed with St. Louis in March 2013. The Cardinals did remove him from the 40-man roster midseason, but made the calculated risk knowing it was unlikely another team would make a waiver claim on a player who's due that much money. Diaz, who has battled several injuries since signing, surged in the second half, batting .333/.404/.574 over his final 45 games, and he should contend for a backup-infielder role next season.

Dean Kiekhefer
Kiekhefer, an Arizona Fall League participant this year, could emerge as a lefty reliever option for the Cardinals in 2016. He profiles as a potential lefty specialist, though his overall numbers in 2015 -- a 2.41 ERA and 1.26 WHIP in 50 games -- show he had plenty of success against all Triple-A hitters. He may be as close to Major League ready as anyone not already on the 40-man roster, so he's an almost certain add.

Luis Perdomo
Perdomo, who represented the Cardinals in the All-Star Futures Game, may not have had standout results in 2015, but he does have intriguing raw talent. In a combined 23 outings (22 starts) with the low Class A and high Class A clubs, Perdomo posted a 3.98 ERA. If the Cardinals don't believe a team could carry him on a Major League roster all season, they may risk leaving him off the 40-man roster for another season. He is the Cardinals' 11th-best prospect, per MLB Pipeline.

Top Prospects: Perdomo, STL

Charlie Tilson
Another AFL participant, Tilson had a solid season in Double-A, hitting .295/.351/.388 with 46 stolen bases while playing primarily in center. He profiles as a potential future fourth outfielder, though the Cardinals will have to decide whether to protect another outfielder on their roster when they already have an abundance of them at the Major League level. He is ranked as the Cardinals' seventh-best prospect, per MLB Pipeline.

Jacob Wilson
Wilson made a strong impression as a non-roster invitee to Cardinals camp last spring, though he didn't carry that momentum into the season. Wilson hit .230/.302/.407 while playing most of the season at Double-A. He does have versatility to play at second and third, and he could be a player the Cardinals want to ensure they retain as infield depth.

Patrick Wisdom
Wisdom's climb stalled some in 2015, as he remained in Double-A for the second straight season. The Cardinals did send him to the AFL and still like his potential as a third baseman. He is the Cardinals' 12th-best prospect, per MLB Pipeline.

Other notable players
C.J. McElroy, Kyle Hald, Kurt Heyer, Ryan Sherriff, Thomas Lee, Breyvic Valera

Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, follow her on Twitter @LangoschMLB, like her Facebook page Jenifer Langosch for Cardinals.com and listen to her podcast. This story was not subject to the approval of Major League Baseball or its clubs.